The present invention relates to a device for manipulating a double-nut arrangement, and a method for setting the toe angle of an automobile wheel using a double-nut arrangement on an eccentric bolt. More specifically, the device is designed for use with a double-nut arrangement, wherein there is an outer nut with a diameter larger than an inner nut. With such an arrangement, the device can be used to adjust the rotational position of the eccentric bolt by turning the inner nut, and to secure the position of the eccentric bolt by maintaining the position of the inner nut while tightening the outer nut.
There are various uses for a double-nut arrangement. Most commonly, a double-nut arrangement is utilized on the threaded portion of a fastener, such as a bolt, to ensure that the secured state of the fastener is maintained. A second nut is generally tightened against a first nut to keep pressure thereon and prevent the first nut from loosening. In this arrangement, each nut is typically of the same relative diameter, although nuts of dissimilar diameter may also be employed.
There may also be the situation, to which the device of the present invention is more particularly directed, wherein the inner nut of a double-nut arrangement is used to adjust the rotational position of the fastener on which it is installed, while the outer nut is used to secure the rotational position of the fastener. Such an arrangement may be utilized in combination with an eccentric fastener element, such as a specialized bolt, so that rotation thereof will accomplish the movement of one or more other elements. This type of double-nut arrangement may be employed in automobile designs, for example, to allow for the adjustment of wheel toe angle.
When used to set wheel toe angle, for example, an assembly comprising an eccentric fastener, such as a bolt, having a head at one end and threads at the other end, an inner nut, and an outer nut may be employed. The inner nut may be adapted to engage a portion of the fastener body near the threaded end. The outer nut may be provided to engage the threaded portion of the fastener, such that the outer nut resides nearer the end of the fastener body than the inner nut. The outer nut preferably also has a diameter that is smaller than that of the inner nut. A disk-shaped flange may be located on both the inner nut and the fastener body, such that when the fastener is rotated, the flanges will rotate along a path eccentric to that of the longitudinal axis of the fastener body. The eccentric movement of the assembly may be used to move an element through which the fastener body passes or, alternatively, to act upon another, adjacent element.
When using such an assembly to set the toe angle of a vehicle wheel, for example, it may be difficult to engage and manipulate both the head of the bolt, to rotate the fastener body and, simultaneously, the outer nut, for securing the rotational position of the fastener assembly. On an automobile, for example, the fastener assembly is typically used on both the driver and passenger sides; resulting in a mirrored orientation from one side to the other. This results in poor ergonomics, both because the bolt head is largely out of sight, and because manipulation of the fastener assembly on one side of the automobile must be performed in a position reversed from that of the other side. Thus, whether the technician is right-handed or left-handed, the technician will be required to work in the opposite manner on one side of the vehicle.
Whatever the application for such a double-nut fastener assembly, it is ergonomically preferable that both adjustment of the fastener""s rotational position and tightening of the fastener can be accomplished from the nut-side of the assembly. In this manner, an operator working with the fastener assembly is not required to find and manipulate the head of the fastener body, which may not be visible. Single-sided manipulation also allows the operation to be performed in a more compact space, and in a position more ergonomically friendly to the person performing the operation.
The device of the present invention allows for both the adjusting and tightening of a double-nut fastener assembly from the nut-side thereof. In the present invention, the fastener employs an inner nut that is unthreaded. A portion of the interior of the inner nut is designed to engage flat sections provided on the fastener body. Therefore, rotation of the inner nut will also produce rotation of the fastener assembly. As a result, the proper rotational position of the fastener assembly can be achieved from the nut-side thereof, and searching for the head of the fastener body is rendered unnecessary. The device of the present invention also allows tightening of the outer nut to be accomplished from the nut-side of the fastener assembly, thereby facilitating securing of the fastener assembly position.
The device of the present invention utilizes a multi-component, double-socket arrangement to perform this task. A first component includes a handle, to which one end of a hollow cylindrical portion is attached. To the opposite end of the hollow cylindrical portion is attached an adjusting socket, which is of appropriate size to engage the inner nut. The portion of the handle in communication with the hollow cylindrical portion has an aperture therethrough, that corresponds in relative location to the inner diameter of the hollow cylindrical portion. The aperture permits a portion of a second component of the device to pass therethrough. The second component comprises an elongated and substantially cylindrical shaft, having a drive connector at a first end and a securing socket at a second end. The drive connector is provided for releasably attaching the second component to a torque exerting device, such as a ratcheting or pneumatic wrench. The securing socket is employed to engage the outer nut. A socket coupler is preferably provided at the second end of the shaft, so that the securing socket may be releasably attached thereto after the shaft has been inserted into the first component. The securing socket is sized to allow its movement within the interior of the hollow cylindrical portion and the first socket, but is preferably of too large a diameter to pass through the aperture in the handle portion of the first component. Similarly, the drive connector is also preferably of too large a diameter to pass through the aperture. Thus, the first component is designed to receive a substantial portion of the second component, and to retain the second component therein once the securing socket has been attached to the cylindrical shaft. Additionally, each of the first and second components remain independently movable after insertion of the second component into the first component. In this manner, the first component can be used to adjust the rotational position of the fastener assembly, and to maintain the desired position while the fastener assembly is secured by the second component acting on the outer nut.